The present invention relates to a surgical cutting instrument. More particularly, it relates to a surgical micro-shaving instrument the distal tip of which is configured to assist in tissue dissection and is particularly useful for inferior turbinate reduction procedures.
Surgical resecting instruments in which an elongate inner member is rotated or oscillated within an elongate outer tubular member has become well accepted in surgical procedures where access to the surgical site is gained via a narrow portal or passage. Typically, the outer tubular member includes a distal end defining a cutting port or window, and the inner member includes a distal end with a cutting tip for engaging and resecting bodily tissue via the cutting window. Proximal ends of the inner and outer members are commonly secured to hubs that, in turn, attach to a handpiece. The handpiece can have a motor for rotating and/or oscillating the inner member relative to the outer tubular member. The cutting tip of the inner tubular member can have various configurations specific to the surgical procedure in question (e.g., resecting, cutting, shaving, abrading, etc.), with the cutting window being suitably configured to cooperate with the particular configuration of the cutting tip. Typically, the inner tubular member defines a lumen so that the loose tissue resulting from a cutting, resecting or abrading procedure can be aspirated from the target site.
The above-described surgical cutting instruments are useful for a number of surgical procedures, especially ear-nose-throat (ENT) operations. One particular ENT procedure relates to treatment of an inferior turbinate in the sinus cavity. The role of inferior turbinate pathology and the reduction of nasal airflow are well known. In short, the inferior turbinate of the sinus cavity may become enlarged or inflamed (e.g., inferior turbinate hypertrophy) for a variety of reasons. This inflammation obstructs the patient""s nasal airway, causing breathing difficulties. In cases where medicinal treatment fails, a preferred surgical treatment entails resecting submucous tissue of the inferior turbinate, thereby reducing the inferior turbinate size. In this regard, available techniques for turbinate reduction include turbinectomy, submucous turbinectomy, inferior turbinoplasty, cryotherapy, submucous electrosurgery, and laser turbinoplasty. Unfortunately, short-term and long-term complications such as bleeding, crusting, synechiae formation, and atrophic rhinitis are often times associated with each of the above-listed techniques, due to sacrifice of mucosa for access to the target site. In light of these potential complications, surgeons have recently begun using the surgical cutting instruments previously described, and in particular a 2-mm surgical shaving instrument, to resect or shave tissue on an inside of the inferior turbinate by puncturing the turbinate anteriorly and then moving the cutting tip in a posterior fashion while resecting the targeted tissue. By resecting the interior tissue, the turbinate heals by shrinking internally, thereby allowing for better nasal airflow.
Use of a surgical micro-resecting or -shaving instrument for treatment of enlarged or inflamed inferior turbinate in the sinus cavity appears quite promising. In fact, a micro-shaving instrument is best able to achieve a primary goal of volumetric reduction of the sub-mucosal vascular stromal tissue with preservation of the overlying respitory epithelium. Unfortunately, currently available instruments for performing inferior turbinectomies have a blunt, distal end that is not conducive to a puncturing-type action. Further, available surgical micro-shaving instruments are configured such that the surgeon must rely solely upon the cutting window to resect the tissue from the bone inside the turbinate of the sinus cavity. This is a difficult and time consuming procedure, as the tissue in question is generally xe2x80x9ctightxe2x80x9d against the bone.
Inferior turbinate reduction with a surgical micro-shaving instrument appears highly viable, and may eliminate the complications otherwise associated with other turbinate reduction techniques. Unfortunately, however, currently available micro-shaving instruments are not designed to satisfy the needs of the inferior turbinate site. Therefore, a need exists for an inferior turbinate surgical micro-shaving instrument.
One aspect of the present invention relates to a surgical micro-shaving instrument including an outer tubular member coaxially maintaining an inner tubular member. The outer tubular member is an elongated body defining a distal section, a proximal section and a central lumen extending from the distal section to the proximal section. The distal section forms an elevator tip and a cutting window. The cutting window is positioned proximal the elevator tip and is connected to the central lumen. The elevator tip terminates at a blade-like edge and is non-blunt. In one preferred embodiment, the elevator tip terminates in a knife edge. Regardless, the elevator tip defines a top surface extending from the elevator window. In one preferred embodiment, the top surface extends in an angular fashion, planar with a plane of the cutting window. In another preferred embodiment, the top surface includes a proximal portion and a distal portion. With this configuration, the proximal portion is planar with a plane of the cutting window. Further, the distal portion extends upwardly in an angular fashion from the proximal portion, defining an obtuse angle therebetween.
During use, the surgical micro-shaving instrument is directed toward the inferior turbinate. The elevator tip is used to puncture the turbinate as well as to dissect tissue away from the turbinate bone, thereby creating improved tissue/instrument engagement.